Feeding mechanism for sewing-machines.



W. H. STBDMAN.

FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED DEC 30, 1908.

Patented Aug. 26, 1913.

v INVBNTEI HIE 4 llllii'l -Hh/l l/d l s/ A H.

UNITED STATES: PATENT OFF ICE! WILLIAM strnn vrnn, 0F HARTFORD, CONNECTICUT, ASSIGNQR TO THE MEnRow MACHINE CQMPANY, 015, HARTFORD, CONNECTICUT, A CORPORATION OF CON- FEEDING MEGHANISM FOB SEWING-MACHINES.

Specification of Letters Patent.

Patented. Aug. 26,1913.

App a i n ed e mb r 3 0%- Se M 469.

To all whom it may concern Be it known that I, WILLIAM H. Srpo- MAN, a citizen of the United States, residing in the city and county of Hartford, State oi Connecticut, have invented certain new and useful Improvements in Feeding Mechfi nism for Sewing-Machines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this SPEC}: fication, and to the figures and letters of ref? erence marked thereon. I

The object of the invention is to provide a work feeding mechanism for sewing machines embodying two feed dogs with means for operating and adjusting them to operate practically either as a single integral feed dog, or as two distinct feed dogs to produce either gathering or stretching of the fabric at the point of stitch formation and the invention consists therein and in various devices and combinations of mechanism as herein after pointed out and claimed.

Feeding mechanism of the character men tioned is especially useful in overseaming machines when operating upon knit goods, which when an ordinary feed is employed, are liable to be stretched at the overseamed edge. To obviate this difiiculty, a pair of feed dogs, each adjustable upon its inde pendent feed bar or carrier have been employed, whereby the goods are fed in front of or to the needle, somewhat faster than they are fed from or in rear of the needle, to produce an overseamed edge corresponding in length with the body of the goods.

The mechanism of this invention is capae ble of operating in the manner just de: scribed and further, is capable of a reversal of such operation, it being desirable when operating upon certain classes of goods to feed them in front of or to the needle more slowly than they are fed in rear of or from the needle to lengthen or stretch the edge.

Briefly, the mechanism of this invention is such as to permit the feed dogs to be ops erated in unison both as to length and timing of feed or with respectively different lengths of feed and with any suitable relative timing,

An embodiment of this invention is illustrated in the drawings, in which it is shown in connection with an overseaming machine o the type described in Letters Patent #725,168, issued to me April 14, 1903.

Throughout the several figures of the drawings similar reference characters indi: cate the same parts.

In the drawingsFigure 1 is a left end elevation, showing the casing of the machine in section. Fig. 2 is a perspective view of the feeding mechanism the casing in which it is mounted being shown broken away. Fig. 3 is a plan view of the needle'plate and the adjacent portion of its support and also shows the'serrated surfaces of the feed dogs and in section the needle.

The stitch forming and feeding mechanisms derive their motions from the drive shaft A The carrier a for the eye pointed needle (1 is pivoted on a shaft a in hearings (L and said carrier is reciprocated by means of a connectingrod a pivotally secured to the carrier a at one end and at the opposite end having connection with an eccentric (not shown) on the shaft A. Cooperating with the needle a are suitable implements not shown herein whereby the formation of overseam stitches be'produced.

The work plate 2' is supported by the cover plate 1, adapted to be secured to the casing. The work plate 2" is shown in Fig. 3 and is provided with suitable feed slots 2' 7? for the passage of the feed dogs and is also pro vided with a slot- 71 for the passage of the needle and with a finger i around which the oversea-m stitches are made.

The letter G denotes the presser foot.

The feeding mechanism is of the four mot-ion type and as already stated these motions are derived from the main shaft A through suitable connections therewith. The feed dog f is mounted on a carrier f which latter is pivotally secured at one end to the upper end of a rocking frame f the latter being in turn mounted on a rod 79 in fixed bearings f formed on or secured to the casing A. The rocking frame f imparts the horizontal reoiprocatory movements to the feed dog f, for which purposes said frame is connected by a rod and strap f with an eccentric f mounted for radial adjustment on the shaft A the position of such adjustment of the eccentric determining the length of feed. The adjustable eccentric is of a well known type of such devices and its adjustability is obtained by securing or forming thereon a dove tail projection or slide f working in a transverse dove tail groove in a collar f mounted on the shaft A Screw adjustment is provided for the eccentric f by means of two screws mounted in the slide f and engaging the drive shaft at opposite points, this construction being not fully shown in the drawings in connection with the eccentric f but corresponding with similar mechanism pro dove tail groove in a collar f mounted on the shaft A and hereinafter fully described. The said adjusting screws for the eccentric f (only one of which is shown in the drawings and denoted by f) are manipulated to change the eccentricity of the eccentric f and thereby alter its throw it being understood that the shaft hole through the eccentric is elongated in the direction of such adjustment.

The carrier f of the fed dog f is provided with a slot or recess constituting a guide way f in which works a block f having a bearing therein for "an eccentric f mounted on the drive shaft A which eccentric and block impart the necessary vertical movements to the feed dog f as will be readily understood.

The mechanism above specifically de scribed is practically identical with similar mechanism of my earlier patent herein above mentioned excepting that the collars f and s are rotatively adjustable, this being a feature of the invention.

The second feed dog and its related mechanism are in general similar to the already described feeding devices, 1'. 6., the letter 8 denotes the just mentioned feed dog which is secured to a feed carrier 8 located at the side of the feed carrier f At one end the carrier 8 is pivotally secured by a pin .9 to the upper end of a rocking frame- 8 similar to the rocking frame f and preferably mounted on the same rod 17 supporting the said frame f as shown in the drawings. The rocking frame 8 imparts the horizontal reciprocatory motions to the feed dog 8 as the former is rocked by means of a strap .9 one end of which is pivoted to the frame 8 by means of the pin 8 and the opposite end of which encircles the eccentric 8 (already mentioned) on the main shaft A As stated the eccentric s is radially adjustable on the shaft A to vary the throw or length of feed of the feed dog 5. The feed eccentric s has attached to it a dove tail projection or slide 8 working in a transverse dove tail groove in a collar 5 rigidly but adjustably mounted on the shaft A as will be explained later. Two screws 8 mounted in the projection s engage and bear against the drive shaft A at opposite points and form a convenient and ready means for shifting the position of the eccentric s with relation to the shaft to give the eccentric greater or less throw, the shaft hole through the feed eccentric'being elongated in the direction of such adjustment.

The lower portion of the carrier 8 is substantially the same as the carrier f 2'. 6., it is provided with a slot or recess constitutin a guide way 8 in which works the block f, the latter being of suflicient width to engage both carriers f and s and acts to operate both of said carriers vertically.

The length of the forward and backward motions of each feed dog is independently cont-rolled by means of the described adjustable eccentrics and the relative timing of these movements may be also controlled by rotatively adjusting the collars f and s relatively to each other upon the shaft A by means of set screws T, or other well known adjustable securing means, so that it is possible to cause the feed dogs to move forward and backward in unison or in any other suitable relations.

The feed dogs f and s are vertically ad justable on their respective carriers f and s and in each instance the feed dog is secured at the forward end of its carrier by a screw t passing through a slot in the feed dog and entering a hole in the end of the carrier. There is preferably tongue and groove connection between each feed dog and its car rier as shown in connection with the feed dog 8 and its carrier 8 The feed dogs f and 8 being secured at the front ends of the carriers rather than at the sides or top, the screws t are readily accessible from the front of the machine and neither carrier is in the way of the feed dog retaining screw of the companion carrier nor has it to be cut away to permit of access to said feed dog retaining screw. 1

The rear feed dog f is shown as having two feed surfaces this being a common con struction and particularly useful in overseaming machines to better control the overseamed edge and to carry away the chain of stitches when the machine is operated without fabric therein.

One of the carriers is preferably somewhat longer than the other that its feed dog may be readily attached to the carrier in advance of the companion feed dog.

It will be understood that the form and size of the feed surfaces will be modified according to requirements.

While this invention is described as applied and adapted to a certain type of overseaming machine it will be understood that it may be used in connection with various types of overseaming devices or other kinds of sewing mechanism.

Having thus described my invention, what I claim as new and desire to secure by Letters-Patent, is:

1. In a sewing machine, feeding mechanism including two feed dogs, two proximate independent carriers each supporting one of the feed dogs, independent rocker frames pivotally mounted end to end on a common axis and at their proximate ends each pivotally connected with one of the carriers, an operating shaft, eccentrics on the shaft one on each side of the carriers, operating connections between the eccentrics and the rocking frames respectively, and mechanism on the shaft between the eccentrics for imparting vertical movements to the carriers.

2. In combination with overseaming devices including a fabric penetrating needle and means for actuating said devices, feeding mechanism including two feed dogs arranged respectively in front and in rear of the path of the needle, an eccentric for each feed dog for imparting backward and forward motions thereto each of said eccentrics being radially and rotatively adjustable relative to its axis of rotation, means for supporting and rotating the eccentrics, means for supporting the feed dogs and connections between the same and the eccentrics and means for raising and lowering the feed dogs simultaneously.

In combination with overseaming devices including a fabric penetrating needle and means for actuating said devices, feeding mechanism including two feed dogs located respectively in front and in rear of the path of the needle, an eccentric for each feed dog for imparting backward and forward motion thereto, a supporting and driving shaft common to said eccentrics and upon which they are mounted and are separately radially and rotatively adjustable, means for supporting the feed dogs and connections between the same and the eccentrics and an eccentric on the said shaft intermediate the two adjustable eccentrics and means between the intermediate eccentric and the feed dogs whereby the latter are raised and lowered simultaneously.

4. In a sewing machine, feeding mechanism including two feed dogs, a carrier for each feed dog, two rocking frames pivotally supported in the machine and having pivotal connection each with one of the carriers respectively, two eccentrics, eccentric connections for each whereby they are respectively connected one with each rocking frame, an eccentric intermediate the said two eccentrics, a block on the said intermediate eccentric engaging both the feed dog carriers and a shaft common to the three eccentrics.

5. In a sewing machine, the combination of a differential feeding mechanism comprising two independent feeding mechanisms and a single rotating shaft common to both, each feeding mechanism including an adjustable throw eccentric adj ustably mounted on the common shaft, a rocker frame fulcrumed on a fixed axis and a link for connecting said rocker frame to the said eccentric, a feed bar having a feed surface secured thereto, the said feed bar and link being pivotally connected to the rocker frame on the same side of its axis, and means for positively imparting rising and falling movements to the feed surface of both feed bars.

WILLIAM H. STEDMAN.

\Vitnesses:

G. W. WRIGHT, CHAs. E. BOND.

copies of this patent may be obtained for five cents each, by addressing the. Commissioner of Patents, Washington, D. O. 

